Field of the Disclosure
The present disclosure, for example, relates to wireless communication systems, and more particularly to extended idle discontinuous reception (eI-DRX) operations.
Description of Related Art
Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code-division multiple access (CDMA) systems, time-division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, and orthogonal frequency-division multiple access (OFDMA) systems.
By way of example, a wireless multiple-access communication system may include a number of base stations, each simultaneously supporting communication for multiple communication devices, otherwise known as user equipments (UEs). A base station may communicate with UEs on downlink channels (e.g., for transmissions from a base station to a UE) and uplink channels (e.g., for transmissions from a UE to a base station).
A UE may also enter into various modes in order to save battery power. For example, a UE may enter into a discontinuous reception (DRX) mode in which communications received by the UE are limited. A DRX mode may be applied in either a connected state (C-DRX) or in an idle state (I-DRX). In each case, the UE limits its reception of communications to specified radio frames within a DRX cycle. A longer DRX cycle results in the UE communicating with a base station less frequently and potentially saving battery power. However, as a DRX cycle becomes longer, there is a risk that communication conditions for the UE may change during the time interval between the specified radio frames. For example, if an I-DRX cycle is long enough, it is possible that a UE could move between coverage areas of different base stations during the I-DRX cycle, meaning that the UE could awake and discover that the UE may have need of participating in a base station handoff operation before the UE can participate in other operations such as paging. In such situations, the UE risks missing a message such as a paging message due to the change in the UE's communication conditions.